I think it's because they are vastly different situations. Lois probably liked (or pretended to like) being called Mad Dog Lane when she went after a story because it showed that she was determined and aggressive. However, three years later, after softening her personal touch, the phrase would seem a bit harsh. And, more importantly, in this case, they aren't refering to her journalistic tenacity, they are using that nickname to portray her as a crazed murderer. Not exactly flattering in any light.
Anni
